Lapping machine



March H 1924. ,46,345 7 W. E. HOKE' LAPPING MACHINE Original Filed Aug. 30, 1918 i atented er, 11,1924.

.WILLIAM E. HOKE, or BALTI oRnlMARYLANn.

L APPING MACEINE.

Original application filed August 30,'1918, Serial No. 252,073. Dvided and this application filed December .9, 1922.

To all who m it 'may concern:

Be it known thatI, WILLIAM E. HOKE, a citizen of the United States, residing at Baltiinore, in the county of Baltimore and axis of the lap, is a ring 42, having therei n a State of Maryland, have invented certain new and useful Improvements in' Lapping Machines, of which the following is a specification. v 4

This invention relates to an apparatus for making articles of various kinds such as' balls, cylinders, perforated articles,` etc., of steel or iron, 'in large numbers, .each article being of precisely the same dimensions as every other article.

Beferring to the drawings:

Fig. 1 is a plan View onthe plane I-I 'of Fig. 2;

Fig. 2 is a section on plane II-H of Fig. l.

In carrying out my invention the articles are brought to final shape by lappng With* a suitable-lap which consists of a sur'ace of wax, Wood, lead, aluminum, copper, iron orsteel having charged into its surface a Suitable abradant such as emery, alundum, carborundum, etc.

. In F igs. 1 and 2, 40 and 41 are annular cylindrical laps having true plane surfaces, the upper lap being arranged'in any'suitable manner to rotate about the axis. be rotated, as by crank 45, eccentric to the series of'circular openings within each of which are retained a number of the balls 44 to be ground. By the eccentric rotation of the plate 42 the balls are rotated and ground between the fixed and rotatory lapping surfaces. This -in'g 42, as shown, has a pivotal connection to the crank so that the plate is free to revolveabout its own axis. This pi'votal connection is only diagrammatically illustrated, but any suitable connection may be used such as' that shown in my prior ap plication, Serial No. 242,482, filed June 28,

As shown, a number of balls are arranged about a central ball 46 which acts as a spacer to hold the balls' away fro the center of the Opening in the ring. As the' ring rotates in an eccentric planetary path, the

balls' are rolled over and over, and in turn impart a rotarymovement to the upper lap. The upper lap, which may of course be weighted f desired, is allowed to rest upon Mounted to Serial No. 605,372. r

the s'urface of the multiplicity of balls being ground, 'and thus acts only to remove up standing inequalities wherever they occur in .the whole group of articles. The upper lap rests freely on the surfaces of the balls so that the grinding action is unrestrained.

This lap 40 may be kept in position by a tain nunber of the balls are transposed in position so 'that they occupy a different position -with reference 'to the ,other balls, the lapping, transposition, andrearrangement of the ball-3 being repeated until all are brought to a uniform size.

The balls are measured after each lapping operation by placing a row of the balls in line as in a grooved receptacle, and the a'ggregate length of the row determined by comparison 'With the-standard. If the balls are 'still too large, they are, after being transposed in 'their relativepositions, subjected to as many lapping operations as may be required to reduce them to exact size.

This application is a division and continuation of my application Serial No. 252,073, filed August 30, 1918.

I claim v 1. A lapping machine comprising a pair of discs having spaced lapping surfaces, a work carrier between said discs'having a pl'urality of apertures therein, and means for effe'cting bodil'y movement between the *work carrierfand the laps in a substantially circular path said machine having one lap unrestrained in movement and each of the openings in the work carrier 'being of a size to loosely hold' a .plurality of articles to be lapped.

2. In alappingmachine, a pair of discs having spaced lappingsurfaces, one of said laps being unrestrained in movement a work carrier'between said discs, Said work' carrier having a plurality of apertures for loosely holding articles to be lapped, with means for separating a group of the articles being operated upon, a crank connected to said carrier and arranged to impart movement to said car'riereccentric to the axis of the discs.

8. In a lapping machine, a pair of discs having spaced lapping rier between said discs, and means for effectnga relatively eccentric planetary movehaving spaced lapping surfaces, a work car-' rier between said discs, and means for effecting a relatively ecoentric planetary movement between said carrier and said discs, said carrier being also rotatable about its own center, and said work carrier having a plurality of apertures for loosely holding surfaces, a work car- V articles to be lapped, with means for holding said articles away from the 'centers of said apertures.

5. A lapping machine including in com'- bination two opposed laps having flat working surfaces, a work carrier positioned between said laps and having work receiving openings therein, each of said openings being of a size to hold a plurality of articles to be lapped, a shaft having a c'ank cen-` trally loosely engaging the work carrier, whereby the work carrier is free to rotate about its own axis and there results bodily movement between the work carrier and laps in a circular path, the plurality of articles in each Opening in the work carrier being free to rot-ate bodily about the axes of the 4 openings so as to execute a substantially planetary movement.

In testimony whereof, I aflix my signature.

WILLIAM E. HOKE. 

